In random access ,each station has right to send the data. However , if more than one station tries to send ,collision will occur .To avoid this collision , protocols came into existence.
In random access method , no stations are superior & none is assigned the control over the other .
When a station has a data to send , it uses a procedure defined by a protocol whether to send or not .
Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations. The three channelization protocols are FDMA, TDMA, and CDMA
Carrier-sense multiple access with collision detection (CSMA/CD) is a media access control method used most notably in early Ethernet technology for local area networking.Carrier-sense multiple access with collision detection is a media access control method used most notably in early Ethernet technology for local area networking. It uses carrier-sensing to defer transmissions until no other stations are transmitting.
Channelization is a multiple-access method in which the available bandwidth of a link is shared in time, frequency, or through code, between different stations. The three channelization protocols are FDMA, TDMA, and CDMA
Carrier-sense multiple access with collision detection (CSMA/CD) is a media access control method used most notably in early Ethernet technology for local area networking.Carrier-sense multiple access with collision detection is a media access control method used most notably in early Ethernet technology for local area networking. It uses carrier-sensing to defer transmissions until no other stations are transmitting.
The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between adjacent network nodes in a wide area network (WAN) or between nodes on the same local area network (LAN) segment.
In the seven-layer OSI model of computer networking, media access control (MAC) data communication protocol is a sublayer of the data link layer (layer 2). The MAC sublayer provides addressing and channel access control mechanisms that make it possible for several terminals or network nodes to communicate within a multiple access network that incorporates a shared medium, e.g. an Ethernet network. The hardware that implements the MAC is referred to as a media access controller.
The MAC sublayer acts as an interface between the logical link control (LLC) sublayer and the network's physical layer. The MAC layer emulates a full-duplex logical communication channel in a multi-point network. This channel may provide unicast, multicast or broadcast communication service.
SLOTTED ALOHA and pure aloha are the category of alohaAkshathaM29
The data link layer is used in a computer network to transmit the data between two devices or nodes. It divides the layer into parts such as data link control and the multiple access resolution/protocol. The upper layer has the responsibility to flow control and the error control in the data link layer, and hence it is termed as logical of data link control. Whereas the lower sub-layer is used to handle and reduce the collision or multiple access on a channel. Hence it is termed as media access control or the multiple access resolutions. ALOHA, an acronym for Advocates of Linux Open-source Hawaii Association, is a multiple access protocol that allows data to be transmitted over a public network channel. It operates within the Medium Access Control (MAC) sublayer of the Open Systems Interconnection (OSI) model.When a sender and receiver have a dedicated link to transmit data packets, the data link control is enough to handle the channel. Suppose there is no dedicated path to communicate or transfer the data between two devices. In that case, multiple stations access the channel and simultaneously transmits the data over the channel. It may create collision and cross talk. Hence, the multiple access protocol is required to reduce the collision and avoid crosstalk between the channels.
ALOHA is a multiple access protocol for transmission of data via a shared network channel. It operates in the medium access control sublayer (MAC sublayer) of the open systems interconnection (OSI) model. Using this protocol, several data streams originating from multiple nodes are transferred through a multi-point transmission channel.
this protocol, all the station has the equal priority to send the data over a channel. In random access protocol, one or more stations cannot depend on another station nor any station control another station. Depending on the channel's state (idle or busy), each station transmits the data frame. However, if more than one station sends the data over a channel, there may be a collision or data conflict. Due to the collision, the data frame packets may be lost or changed. And hence, it does not receive by the receiver end.
In ALOHA, each node or station transmits a frame without trying to detect whether the transmission channel is idle or busy. If the channel is idle, then the frames will be successfully transmitted. If two frames attempt to occupy the channel simultaneously, collision of frames will occur and the frames will be discarded. These stations may choose to retransmit the corrupted frames repeatedly until successful transmission occurs
In pure ALOHA, the time of transmission is continuous. Whenever a station has an available frame, it sends the frame. If there is collision and the frame is destroyed, the sender waits for a random amount of time before retransmitting it.
Slotted ALOHA reduces the number of collisions and doubles the capacity of pure ALOHA. The shared channel is divided into a number of discrete time intervals
The data link layer, or layer 2, is the second layer of the seven-layer OSI model of computer networking. This layer is the protocol layer that transfers data between adjacent network nodes in a wide area network (WAN) or between nodes on the same local area network (LAN) segment.
In the seven-layer OSI model of computer networking, media access control (MAC) data communication protocol is a sublayer of the data link layer (layer 2). The MAC sublayer provides addressing and channel access control mechanisms that make it possible for several terminals or network nodes to communicate within a multiple access network that incorporates a shared medium, e.g. an Ethernet network. The hardware that implements the MAC is referred to as a media access controller.
The MAC sublayer acts as an interface between the logical link control (LLC) sublayer and the network's physical layer. The MAC layer emulates a full-duplex logical communication channel in a multi-point network. This channel may provide unicast, multicast or broadcast communication service.
SLOTTED ALOHA and pure aloha are the category of alohaAkshathaM29
The data link layer is used in a computer network to transmit the data between two devices or nodes. It divides the layer into parts such as data link control and the multiple access resolution/protocol. The upper layer has the responsibility to flow control and the error control in the data link layer, and hence it is termed as logical of data link control. Whereas the lower sub-layer is used to handle and reduce the collision or multiple access on a channel. Hence it is termed as media access control or the multiple access resolutions. ALOHA, an acronym for Advocates of Linux Open-source Hawaii Association, is a multiple access protocol that allows data to be transmitted over a public network channel. It operates within the Medium Access Control (MAC) sublayer of the Open Systems Interconnection (OSI) model.When a sender and receiver have a dedicated link to transmit data packets, the data link control is enough to handle the channel. Suppose there is no dedicated path to communicate or transfer the data between two devices. In that case, multiple stations access the channel and simultaneously transmits the data over the channel. It may create collision and cross talk. Hence, the multiple access protocol is required to reduce the collision and avoid crosstalk between the channels.
ALOHA is a multiple access protocol for transmission of data via a shared network channel. It operates in the medium access control sublayer (MAC sublayer) of the open systems interconnection (OSI) model. Using this protocol, several data streams originating from multiple nodes are transferred through a multi-point transmission channel.
this protocol, all the station has the equal priority to send the data over a channel. In random access protocol, one or more stations cannot depend on another station nor any station control another station. Depending on the channel's state (idle or busy), each station transmits the data frame. However, if more than one station sends the data over a channel, there may be a collision or data conflict. Due to the collision, the data frame packets may be lost or changed. And hence, it does not receive by the receiver end.
In ALOHA, each node or station transmits a frame without trying to detect whether the transmission channel is idle or busy. If the channel is idle, then the frames will be successfully transmitted. If two frames attempt to occupy the channel simultaneously, collision of frames will occur and the frames will be discarded. These stations may choose to retransmit the corrupted frames repeatedly until successful transmission occurs
In pure ALOHA, the time of transmission is continuous. Whenever a station has an available frame, it sends the frame. If there is collision and the frame is destroyed, the sender waits for a random amount of time before retransmitting it.
Slotted ALOHA reduces the number of collisions and doubles the capacity of pure ALOHA. The shared channel is divided into a number of discrete time intervals
Introduction to Multiple Access Protocol.pptxupamatechverse
Data link layer is divided into two sub layers:
Logical link control (LLC) layer: The upper sub layer is responsible for data link control i.e. for flow and error control.
Media access control (MAC) layer: The lower sub layer is responsible for resolving access to the shared media. If the channel is dedicated, we do not need the lower sub layer.
This is the bottom sublayer of the Data Link Layer. This Chapter is especially relevant for LANs.
4.1 The Channel Allocation Problem
How to allocate a single channel among multiple users.
4.2 Multiple Access Protocols
How to handle contention for the use of a channel.
4.3 IEEE Standards for LANs
How do the protocols of the last sections apply to real systems. Here we talk about the actual standards in use.
4.4 Bridges
Ways of connecting networks together.
4.5 High Speed LANs
Directions in high speed networks.
Similar to RANDOM ACCESS PROTOCOL IN COMMUNICATION (20)
About
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Technical Specifications
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
Key Features
Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
• Remote control: Parallel or serial interface
• Compatible with MAFI CCR system
• Copatiable with IDM8000 CCR
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
Application
• Remote control: Parallel or serial interface.
• Compatible with MAFI CCR system.
• Compatible with IDM8000 CCR.
• Compatible with Backplane mount serial communication.
• Compatible with commercial and Defence aviation CCR system.
• Remote control system for accessing CCR and allied system over serial or TCP.
• Indigenized local Support/presence in India.
• Easy in configuration using DIP switches.
Final project report on grocery store management system..pdfKamal Acharya
In today’s fast-changing business environment, it’s extremely important to be able to respond to client needs in the most effective and timely manner. If your customers wish to see your business online and have instant access to your products or services.
Online Grocery Store is an e-commerce website, which retails various grocery products. This project allows viewing various products available enables registered users to purchase desired products instantly using Paytm, UPI payment processor (Instant Pay) and also can place order by using Cash on Delivery (Pay Later) option. This project provides an easy access to Administrators and Managers to view orders placed using Pay Later and Instant Pay options.
In order to develop an e-commerce website, a number of Technologies must be studied and understood. These include multi-tiered architecture, server and client-side scripting techniques, implementation technologies, programming language (such as PHP, HTML, CSS, JavaScript) and MySQL relational databases. This is a project with the objective to develop a basic website where a consumer is provided with a shopping cart website and also to know about the technologies used to develop such a website.
This document will discuss each of the underlying technologies to create and implement an e- commerce website.
Student information management system project report ii.pdfKamal Acharya
Our project explains about the student management. This project mainly explains the various actions related to student details. This project shows some ease in adding, editing and deleting the student details. It also provides a less time consuming process for viewing, adding, editing and deleting the marks of the students.
Hierarchical Digital Twin of a Naval Power SystemKerry Sado
A hierarchical digital twin of a Naval DC power system has been developed and experimentally verified. Similar to other state-of-the-art digital twins, this technology creates a digital replica of the physical system executed in real-time or faster, which can modify hardware controls. However, its advantage stems from distributing computational efforts by utilizing a hierarchical structure composed of lower-level digital twin blocks and a higher-level system digital twin. Each digital twin block is associated with a physical subsystem of the hardware and communicates with a singular system digital twin, which creates a system-level response. By extracting information from each level of the hierarchy, power system controls of the hardware were reconfigured autonomously. This hierarchical digital twin development offers several advantages over other digital twins, particularly in the field of naval power systems. The hierarchical structure allows for greater computational efficiency and scalability while the ability to autonomously reconfigure hardware controls offers increased flexibility and responsiveness. The hierarchical decomposition and models utilized were well aligned with the physical twin, as indicated by the maximum deviations between the developed digital twin hierarchy and the hardware.
Immunizing Image Classifiers Against Localized Adversary Attacksgerogepatton
This paper addresses the vulnerability of deep learning models, particularly convolutional neural networks
(CNN)s, to adversarial attacks and presents a proactive training technique designed to counter them. We
introduce a novel volumization algorithm, which transforms 2D images into 3D volumetric representations.
When combined with 3D convolution and deep curriculum learning optimization (CLO), itsignificantly improves
the immunity of models against localized universal attacks by up to 40%. We evaluate our proposed approach
using contemporary CNN architectures and the modified Canadian Institute for Advanced Research (CIFAR-10
and CIFAR-100) and ImageNet Large Scale Visual Recognition Challenge (ILSVRC12) datasets, showcasing
accuracy improvements over previous techniques. The results indicate that the combination of the volumetric
input and curriculum learning holds significant promise for mitigating adversarial attacks without necessitating
adversary training.
Sachpazis:Terzaghi Bearing Capacity Estimation in simple terms with Calculati...Dr.Costas Sachpazis
Terzaghi's soil bearing capacity theory, developed by Karl Terzaghi, is a fundamental principle in geotechnical engineering used to determine the bearing capacity of shallow foundations. This theory provides a method to calculate the ultimate bearing capacity of soil, which is the maximum load per unit area that the soil can support without undergoing shear failure. The Calculation HTML Code included.
2. • Introduction
• Problem Statement
• History
• Need for Random access
• Functions
• What is ALOHA & CSMA?
• Flow Chart
• Simulated Graphs
• Advantages
• Limitations
• Applications
• Future Scope
• Conclusion
• References
Contents
3. In random access ,each station has right to send the data.
However , if more than one station tries to send ,collision
will occur .To avoid this collision , protocols came into
existence.
In random access method , no stations are superior &
none is assigned the control over the other .
When a station has a data to send , it uses a procedure
defined by a protocol whether to send or not .
Introduction
4. When 2 users transmit the data packets at the
same time , collision occurs & these packets
are destroyed .
To avoid this , random access protocol has
been adopted .
Problem Statement
5. The development of ALOHA network
commenced in 1968 at the University of
Hawaii by Norman Abramson.
It became operational in 1971 .
During 1980’s the frequencies were assigned
for mobile medium .
In 1985, frequencies were made available for
WIFI facilities .
History of ALOHA
6. Need For Protocol
When two computers are connected via
single connection , the data collision takes
place .
Hence to avoid , a set of rules & regulations
are needed which are called the protocols.
7. Describes the rules that govern
the transmission of data over the
communication network.
Provides a method for orderly and
efficient exchange of data between the
sender and the receiver.
Functions of Protocol
8. ALOHA is for coordinating & accessing to
share communication in network channel.
It is the simplest collision resolution
protocol .
What is ALOHA ?
9. 1.Pure Aloha:
This is the original version of Aloha .
2.Slotted Aloha:
This is the modified version of pure
Aloha.
Types of Aloha
10. What is Pure Aloha ?
Whenever a station has a data , it transmits.
When 2 or more stations transmit data at same time ,
there is a collision .Hence, the sender waits a random
amount of time & then re-transmit the data again .
The waiting time is random , otherwise the same packet
will collide again .
11. What is Slotted Aloha ?
Slotted ALOHA was invented to improve the efficiency of
pure ALOHA as collisions in Pure ALOHA are very high .
In slotted ALOHA , the time is divided into discrete intervals
called slots .
Station can send a frame only at the beginning of the slot &
only one frame is sent in each slot .
23. Comparison between Pure &
Slotted Aloha
The chances of collisions are more in
Pure ALOHA as compared to Slotted
ALOHA .
Slotted ALOHA is more efficient as
compared to Pure ALOHA .
24. Advantages of ALOHA
Packet contention technique
Single active node can continuously transmit at full
rate .
Highly decentralized
Simple protocol
26. What is CSMA ?
CSMA protocol was developed to overcome the
problem found in ALOHA i.e. to minimize the chances
of collision to improve the performance .
CSMA is a network access method used on shared
network topologies .
It is based on the principle of ‘carrier sense ’ .
29. If the channel is idle, station transmits the frame, if busy
senses the channel after random time.
This protocol reduces the chance of collision but longer
delays.
It is a non - aggressive transmission algorithm.
Non- Persistence
30. This protocol is called 1 – Persistence because the station
transmits with probability of 1. When it finds the
channel idle without any collision , station continuously
sense the channel until it becomes free.
It is an aggressive transmission algorithm.
1 - Persistence
35. Out of these 2-types of CSMA it is found
that Non-persistence CSMA performs the
best.
Summary of CSMA
36. Low-data-rate tactical satellite communications networks by
military forces.
In subscriber-based satellite communications networks.
Mobile telephony call setup
Set-top box communications
In the contactless RFID technologies.
Applications
37. Research is to be made to avoid any security
breach & improvement in packet delivery
efficiency .
Future Scope
38. Conclusions
Computer networks & protocols have
changed the humans working &
communication.
The digital network is empowering us for
future.
39. References
www.My reading room/aloha protocol.com
Protocol – oriented programming , Jon Hoffman
www.searchnetworking.techtarget.com
ALOHA Random Access that Operates as a
Rateless Code domir Stefanovi´c, Member, IEEE, Petar Popovski,
Senior Member, IEEE 7-Aug,2013
Throughput Analysis of Wireless Relay Slotted ALOHA Systems
with Network Coding Daisuke Umehara, Tomoya Hirano, Satoshi
Denno, and Masahiro Morikura Graduate School of Informatics,
Kyoto University Yoshida-honmachi, Sakyo-ku, Kyoto 606-8501,
Japan-IEEE -2016
http://users.cs.cf.ac.uk/Dave.Marshall/Internet/node41.html
